Equipment for a change of rotary gobos

ABSTRACT

For lighting equipment for illumination of theatre and show stages and platforms there is designed an equipment for change of rotary gobos comprising a carrier disc supporting interchangeable segments with the gobos. The individual segments ( 2 ) are attached at the carrier disc ( 1 ) by central holding means, each segment ( 2 ) being provided with means for setting the segment ( 2 ) on the carrier disc ( 1 ). Each segment ( 2 ) is provided with a lamella ( 3 ) for attachment in the central holding means. The central holding means comprise a system of flexible fingers ( 10 ) in a fan-shaped arrangement, the fingers ( 10 ) being at inside ends fixed to the carrier disc ( 1 ) and on the outside free ends adapted to allow for insertion of the segment lamellas ( 3 ) between the fingers ( 10 ) and the carrier disc ( 1 ).

TECHNICAL FIELD

The invention relates to an equipment for a change of rotary gobosfurnished with a carrier disc supporting interchangeable segments withthe gobos,

BACKGROUND OF THE INVENTION

The expression gobo relates to an image which is to be projected as aslide within a comparatively great distance. Due to a high temperatureof the respective light source such an image is created on a metal,glass or any suitable base. To increase the achieved effect the goobosrotate, as moving image attracts more attention. Rotary gobos need notto rotate continuously, therefore their rotation depends upon activationof a drive motor. Generally speaking there exist two basic types ofrotary gobo systems, which are applied with minor or major divergences.By the first system gobos are placed on a carrier disc and the gobos areinterchanged. Such a system is technologically simple and cheap, butfrom a practical point of view it is very uncomfortable. In general alighting equipment offer very little space for any manipulation andoften special tools are necessary. This simple design is used preferablyfor cheap equipment. By the second system the carrier disc is furnishedwith mutually independent segments, one segment for each gobo, and thereare changed complete segments. In most cases each segment has a specialbearing with grooves matching with counter-pieces on the carrier disc.This design is very demanding on manufacture technology. It is an objectof the invention to simplify the design of attachment of gobos at thecarrier disc and to facilitate the change procedure.

DISCLOSURE AND OBJECT OF THE INVENTION

The foregoing problems are solved by an equipment for a change of rotarygobos comprising a carrier disc supporting interchangeable segments withthe gobos in accordance with the present invention the individualsegments being attached at the carrier disc by central holding means,each segment being provided with means for setting the segment on thecarrier disc. Further in accordance with the present invention eachsegment may be provided with alamella for attachment in the centralholding means. In a preferred embodiment the central holding meanscomprise a system of flexible fingers in a fan-shaped arrangement. Thefingers are at inside ends fixed to the carrier disc and on the outsidefree ends adapted to allow for insertion of the segment lamellas betweenthe fingers and the carrier disc. The fingers may be at their insideends integrated into one unit. The number of fingers within the unitcorresponds to a number of segments to be supported by the carrier disc.Still further in accordance with the invention each segment is providedwith a bearing supporting a driver with a gobo. The bearing inside ringis provided for by the driver outer rim and the bearing outside ring isattached to the segment lamella by dismountable connection means. Thedriver further comprise a flange with a spur toothing, designed forengaging with a mechanism for rotation of the gobos. Dismountableconnection means for attachment of the bearing outer ring on the lamellamay be preferably ublised as means for setting the segment on thecarrier disc. The carrier disc may be further provided with circularapertures allowing for lighting of gobos, the apertures having theircentres located at a common pitch circle and being along own perimeterprovided with means for engaging with means for setting the segments onthe carrier disc.

According the first aspect of the invention there is provided a simpleseating of a segment with gobos on the carries disc and changing of thegobos is a very simple and easy procedure. According to another aspectof the invention the presented solution is also technologically simplewith little manufacturing costs.

BRIEF DESCRIPTION OF THE DRAWINGS

By way of examples the invention will be now described with reference tothe accompanying drawing. On

FIG. 1 there is presented an axonometric view from above on a carrierdisc with seven segments, one of which is in an outside position and

FIG. 2 show and an axonometric view from underneath on the carrier discaccording to FIG. 1.

FIG. 3 is an axonometric view on one segment in a disassembled state.

FIG. 4 presents an axonometric view on a carrier disc supporting sixsegments and

FIG. 5 represents an axonometric view on a carrier disc with fivesegments.

DESCRIPTION OF PREFERRED EMBODIMENTS

Referring to FIG. 1, there is shown an equipment for a change of rotarygobos comprising a carrier disc 1 on which there are arrangedinterchangeable segments 2 with gobos. On all accompanying drawingsgobos are presented simply as blank fields. In the embodiment presentedon FIG. 1 the carrier disc 1 is equipped with seven segments 2 and onefree position, which serves for direct illumination by white, non-colourlight.

All segments 2 are by central holding means attached at the carrier disc1. Basic part of each segment 2 is made of a shaped lamella 3, the freepart of which serves for attachment of the segment 2 in the centralholding means. The gobo is fixed in a driver 6 seating in ball bearing.Dismountable connection means, like screws 4 with cylindrical head inthe depicted embodiment, serve for securing a ball bearing outside ring5 on the lamella 3 of each segment 2. The bearing balls are freelylocated in the bearing outside ring 5, while the bearing inside ring isprovided for by a driver 6 outer rim. The driver 6 seating is thus of avery simple design when compared with a standard ball bearingarrangement, nevertheless the function of a rotary gobo is fullyretained. The driver 6 is provided with a flange Z having a spurtoothing for engagement with a mechanism for rotation of the gobos.

The carrier disc 1 is provided with apertures 9, the centers of whichare placed on a common pitch circle. The apertures 9 allow for a lightbeam to go through the gobos or just through the carrier disc 1, as thecase may be.

Each segment 2 is provided with means for setting a segment 2 on thecarrier disc 1. Preferably the means for setting a segment 2 on thecarrier disc 1 are provided for by the dismountable connection means forattachment of a ball bearing outside ring 5 on the lamella 3. In thediscussed embodiment the means for setting a segment 2 on the carrierdisc 1 are provided for by the cylindrical heads of the screws 4. Toachieve a proper position of the segment 2 on the carrier disc 1 thescrew 4 heads match with recesses 8 made along a perimeter of respectiveaperture 9 in the carrier disc 1. In the embodiment shown on FIG. 1 andFIG. 2 there are used three screws 4 for each segment 2 and thereforeeach aperture 9 has three recesses 8 distributed along its perimeter andspaced apart with respect to distribution of the screws 4. There may beused a different number of the screws 4, but basically two of them aresufficient. Instead of the above described construction the means forsetting a segment 2 on the carrier disc 1 may be provided for also byanother means known as such.

The central holding means comprise a system of radially extendingflexible fingers 10 in a fan-shaped arrangement. The fingers 10 are atinside ends attached to the carrier disc 1, preferably by rivets, and onthe outside free ends 11 bent upwards to facilitate insertion of segmentlamellas 3 between the fingers 10 and the carrier disc 1 body. Number offingers 10 corresponds to the number of the segments 2, but it ispossible for one finger 10 to secure position of more than one segment2. Preferably the inside ends of all the fingers 10 are integrated intoone piece. In a place corresponding to a free position on the carrierdisc 1 there is no finger 10 and the space is kept free. To improvepressing forces produced by the central holding means upon the segment 2lamellas 3 the fingers 10 may be provided with a pressure disc 12located in their central part common for all the fingers 10, aspresented on FIGS. 4 and 5.

To further facilitate insertion of the segment lamella 3 under thefinger 10 of the carrier disc 1 one of the recesses 8 is carried out insuch a way, that a centre of such a recess 8 is located at a radialgoing through the carrier disc 1 centre, as it is performed by theembodiments illustrated on FIGS. 1, 2, 4 and 5. By a larger number ofsegments 2, usually seven and more, the driver 6 outside contour edgesare cut off, as shown on FIGS. 1 and 2. By a small number of thesegments 2, the inside edge 13 of the lamella 3 is of an arc shape for abetter fit under the central holding means.

INDUSTRIAL APPLICATIONS

The present invention is designed for lighting equipment, especially forillumination of theatre and show stages and platforms etc.

1. Equipment for change of rotary gobos comprising a carrier discprovided with circular apertures (9) allowing for lighting of gobos andfurnished with resilient holding means to support interchangeablesegments with the gobos, characterised in, that each segment (2) isprovided with a lamella (3) for attachment in the holding means and withmeans is for setting the segment (2) on the carrier disc (1). 2.Equipment for a change of rotary gobos according to claim 1,characterised in, that the holding means comprise a system of flexiblefingers (10) in a fan-shaped arrangement, the fingers (10) being atinside ends fixed to the carrier disc (1) and on the outside free endsadapted to allow for insertion of the segment lamellas (3) between thefingers (10) and the carrier disc (1).
 3. Equipment for a change ofrotary gobos according to claim 2, characterised in, that the fingers(10) are at their inside ends initegrated into one unit, while thenumber of fingers (10) within this unit corresponds to the number ofsegments (2) to be supported by the carrier disc (1).
 4. Equipment for achange of rotary gobos according to claim 1, characterised in, that eachsegment (2) is provided with a bearing supporting a driver (6) with agobo, the bearing inside ring being provided for by the driver (6) outerrim and the bearing outside ring (5) being attached to the segmentlamella (3) by dismountable-connection means, while the driver (6)comprise a flange (7) with a spur toothing.
 5. Equipment for a change ofrotary gobos according to claim 1 or 4, characterised in, that the meansfor setting the segment (2) on the carrier disc (1) comprisedismountable-connection means for attachment of the gobo bearing outerring (5) on the lamella (3).